She was born with a condition called uterus didelphys, which means she developed two wombs, but doctors had warned her that she was unlikely to become pregnant in both.

After their early birth the triplets had to stay in hospital for nine weeks, but are now doing fine at home with Hanna and her partner Mick Faulkner, 23, in Devon in southwest England.

"We are just over the moon at how healthy and happy the girls are," she said. "They are three lovely and incredible children, all with very different personalities.

"Gracie seems to be the ringleader -- maybe because she grew up in her own womb. She is very determined and independent, always wanting her food before the others and to do things first," she said.

Doctors say there are only 70 women in the world known to have become pregnant in two wombs, and this is the first reported case of triplets.

"This is so rare you cannot put odds on it," said Ellis Downes, consultant obstetrician at Chase Farm Hospital in London. "I have never heard of this happening anywhere ever before - it is quite amazing.

"Women with two wombs have conceived a baby in each womb before but never twins in one and a singleton in the other. It is extremely unusual."